<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="https://unpkg.com/vue@3/dist/vue.global.js"></script>
    <style>
        .aaa{
            border: 1px solid yellow;
        }
        .bbb{
            width: 100px;
        }
        .ccc{
            height: 100px;
        }
        .ddd{
            background-color: red;
        }
    </style>
</head>
<body>
    <div id="box">
        <div :style="{background:'red'}">zqsl</div>
        <div :style="{backgroundColor:'red'}">zqsl</div>
        <div :style="{'background-color':'red'}">zqsl</div>
        <div :style="style">zqsl</div>
        <div :style="[styleobj1, styleobj2]">zqsl</div>
    </div>
    <script>
        var obj = {
            data() {
                return {
                    style:{
                        backgroundColor:'yellow',
                        'font-size':'20px'
                    },
                    styleobj1:{
                        backgroundColor:'yellow'
                    },
                    styleobj2:{
                        'font-size':'20px'
                    }
                }
            }
        }
        var app = Vue.createApp(obj).mount('#box')
    </script>
</body>
</html>